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Soldiers assigned to a cannon company in the 90th Infantry Division fire an M3 105mm howitzer during fighting near Carentan, France, June 11, 1944. |
by Ralph Bennett
By the beginning of July 1944, the invasion was hanging fire. Cherbourg had fallen, but St. Lô and Caen—primary objectives of the Americans and British respectively—still resisted capture and the bridgehead was nowhere more than twenty-five miles deep and occupied only a fifth of the area planned for the first month. It was not yet clear how gravely the British attack across the river Odon (Epsom) had weakened the German armor, nor that it had in fact forestalled their last effort to break the Allied front, and an American attempt to seize the St. Lô–Coutances road as a start line for further operations failed on 3 and 4 July. Churchill was accusing Montgomery of going too slowly and Eisenhower warning him to avoid stalemate—a charge soon to be repeated by newspapers in the United States. The first exhilaration of the landings had passed and a reaction had set in not to be dissipated until the brilliant victories of 25 July which took the Allies to the banks of the Seine before the end of August.
General Patton was Waiting
In early July no one but their staffs knew that Bradley and Montgomery were confidently laying plans for the breakout from the bridgehead (Cobra on the Allied right, prefaced by Goodwood on the left) while Caen was at last falling on 10 July, but on the other hand there was always the risk of a move of German tanks from the British to the American sector, where the main thrust had always been intended. Nor did more than a few yet know that Gen. George Patton and his Third Army staff were waiting ready to spearhead the great advance, but were for the moment lying doggo somewhere in the Côtentin in order to preserve the illusion that he commanded an army group in Kent poised for descent at any moment on the coast round Calais—a deception designed to induce the Germans to retain large forces there to meet an imaginary assault rather than shift them to Normandy to hinder the Allied build-up. Above all, no one at all on the Allied side could know that by the end of June Rundstedt had already concluded that the only sensible course of action left was to sue for peace (for which advice Hitler dismissed him on 2 July) nor that his successor as Commander-in-Chief West, von Kluge—who had at first been more sanguine—and Rommel (until injury removed him on 17 July) were now repeatedly warning the Führer that the cordon stretched round the invaders might soon snap irretrievably. Things like this were only said at high-level staff discussions or in secret telephone conversations, and so remained hidden from the Allied command.
How much, then, did Eisenhower and his immediate subordinates know from their intelligence sources about German hopes and fears as they planned and executed the breakout from the bridgehead and the encirclement of von Kluge’s armies during the next few weeks?
The ULTRA signals (based on the decoding of wireless messages between German headquarters enciphered with the supposedly invulnerable Enigma machine) have been released from the secrecy hitherto surrounding them, and show the Allied command knew Hitler’s plans for counterattack almost as soon as the German commanders themselves.
The account which follows is derived almost entirely from these signals; a considerable number of those quoted were dispatched to Allied commanders in the field within three or four hours of the time of origin of the German messages underlying them, and most of the remainder within ten or twelve hours.
Decodable Enigma Messages
Not until the landings brought mobile warfare were the Germans forced to stop relying on telephones and teleprinters for most of their military communications in France and instead to fill the air with decodable Enigma messages, but even before D-Day ULTRA’s best information had concerned the American sector. This occurred once more when something like siege conditions developed in the British sector round Caen towards the end of June, bringing land lines into use again there while radio was still necessary further west. Battle contacts were establishing the main identities among the opposing divisions along the whole front, but it was a happy chance which provided the absolutely reliable confirmation of ULTRA’s almost daily reports of the whereabouts of corps and divisional headquarters in just the area where accurate knowledge could be of most benefit and at just the time when it was most needed. Thus the enemy’s line-up could be kept under constant review and changes in it noted as soon as they occurred—even sooner if (as often happened) we intercepted, decoded and re-transmitted the order for a division to move from one position to another before the move itself actually took place.
There was an excellent example of this at the end of the first week in July. The German defense had by now settled into a simple pattern: infantry had the task of containing U.S. First Army in the west, while the armor was concentrated round Caen in the belief (constantly reiterated in ULTRA signals) that a British drive towards Paris would soon trigger off the Calais landing which the deception planners had labored to suggest. Meanwhile, the U.S. 8th Corps’ thrust for Coutances caused great alarm although it did not reach its objective. ULTRA several times reported the German 84th Corps and 2nd Parachute Corps or their subordinate divisions complaining that heavy casualties had consumed all their reserves, so that they would not be able to hold the line against superior American infantry if the offensive continued; further, that they were all short of petrol and ammunition and that in the opinion of 2nd Parachute Corps “German fighters must operate at least for short periods of the day if we are to resist Allied pressure” (a bitter pill for Göring, since this was one branch of his Luftwaffe criticizing another, but even Göring was in the same week compelled to admit that air operations had been restricted by ‘intolerable losses’).
This was encouraging news for Bradley as he planned his devastating stroke. But had his unsuccessful push for Coutances drawn so much attention to this part of the front that von Kluge would accept the risk to Paris and transfer armor from his right wing to his left?
At 1730 on 7 July, it is now known, von Kluge decided to take the risk by moving the crack Panzer Lehr armored division to the American front. At 2300 his decision went over the air in a radio message ordering the division to move to a point west of St. Lô. (ULTRA had been keeping track of it on the banks of the Odon, most recently just twenty-four hours earlier). This message was decoded and transmitted as an ULTRA signal before 0700 the following morning, less than eight hours later. The divisional staff was on the way during the afternoon of 8 July, but the main body did not reach its destination until the following day, nor was it ordered to attack along the Vire–Taute canal until dusk on 10 July. Thus ULTRA had given at least thirty-six hours’ warning of one of the major tactical changes in the battle of Normandy—the first transfer of armor from the British to the American sector. The chance of battle now enabled it to do better still: something delayed Panzer Lehr’s attack until the small hours of 11 July, by which time the ULTRA signal announcing it (which could hardly have been delivered by dusk) had been in Omar Bradley’s hands for four or five hours, long enough for him to prepare appropriate countermeasures. The American War History relates “The Panzer Lehr counterattack had been a dismal and costly failure” which only delayed American operations by twenty-four hours.
The next ten days were filled with battles through the hedgerows for St. Lô and the St. Lô–Periers road, the capture of which were essential in order to secure the revised start line for Cobra. ULTRA’s main contribution here was a series of clear indications that the German defenders, tenaciously though they fought, were nearing exhaustion and were becoming so thin on the ground that they would not be able to withstand the decisive blow. It would be too much to say that ULTRA intelligence guaranteed the sweeping success of Cobra in advance, but fair to suggest that those who launched it could be morally certain that it would blast such a hole in the German front that—since there was no second line of defense—it was a matter of pure speculation where the resultant advance would stop.
On the same day that Panzer Lehr made its abortive attack, 2nd Parachute Corps “scraped together its last reserves” to build new defenses round St. Lô but felt that it would not be able to repel any more attacks unless reinforced, for 3rd Parachute Division’s experiences that day had shown how “even the best troops” could not stand up against material superiority but could only hold on to the last as Hitler had ordered and let themselves be shot to pieces at their posts. Four days later 2nd Parachute Corps struck the same note even more somberly: Casualties had so depleted its ranks that “even the bravest troops cannot prevent a breakthrough” should the attack be renewed. On the 18th, as the battle for St. Lô rose to a crescendo, 3rd Parachute Division and 352nd Infantry Division were so exhausted by weeks of hard fighting that the corps’ left flank was open and unprotected for thirty-six hours until the line could be drawn back to compensate. Finally, in the brief lull between the fall of St. Lô on 20 July and the opening of Cobra five days later, 2nd Parachute Corps forecast that if the Allies attacked again as violently as before they would certainly break through because there was nothing capable of stopping them.
Over towards the west coast 84th Corps had the same sorry tale to tell though ULTRA reported it less frequently. Artillery and air bombardment had so reduced its fighting power by 14 July, and casualties among officers had been so heavy, that the corps could no longer guarantee to hold its line and some units were already giving ground. This was after strenuous efforts by battle groups of the 2nd SS Panzer Division had managed to prevent the front from collapsing but had left the division dangerously short of petrol and ammunition and cost it twenty-two tanks, seven guns and seven lorries.
Confirmation that the infantry lines through which Cobra was to drive a path were extremely fragile came in a series of casualty returns and—most strikingly—in an exchange between the commander of the 2nd Parachute Corps, Meindl, and Gen. Student, the hero of the 1941 air landing on Crete who now commanded the Parachute Army in Germany; their correspondence was in the hands of Eisenhower, Montgomery and Bradley just as Cobra got underway. Meindl complained on 20 July that the fighting power of his paratroops was dwindling steadily and that two requests for new drafts had gone unanswered; the critical situation of the last few days had forced him to commit the few replacements he had received as soon as they arrived—with the result that ninety percent of them became casualties in a very short time, because they were young, untrained men, most of whom had never thrown a hand grenade, fired more than a few rounds of live ammunition or learned much about machine guns, entrenching tools and camouflage.
Even after making allowance for the pardonable exaggerations of a general anxious to persuade his superiors of his plight in order to get their help, this message had a two-fold value: it confirmed that the divisions, on what would in a few days become the left flank of the American thrust, were incapable of mounting an immediate or effective counterattack, and it also betrayed a gradual decline in the quality of the handful of parachute divisions which now constituted almost the only completely reliable German infantry. Student’s reply can have brought but small comfort: 2,500 volunteers were being sent off, he said, but Meindl must remember that the chief reason for the present difficulties was the constant demand for paratroops on all fronts. Meindl then asked that 1,000 of the men be sent to a training depot at home, so that in the end the 3rd Parachute Division (which had been sixty-five percent under strength ten days earlier) got only 1,500 replacements before the attack.
It can therefore be confidently asserted that the American commanders who delivered the decisive blow already knew from ULTRA the answers to several of the questions about the location and strength of German reserves and their ability to mount an armored counterattack which the American War History says were exercising the minds of their intelligence officers about 20 July. Moreover, when the plotters’ bomb failed to kill Hitler that same day, they could deduce that von Kluge would now be compelled to keep looking over his shoulder to see what repercussions the hunt for traitors might have on his own chances of survival, and that this, coming on top of his knowledge that the troops at the base of the Cherbourg peninsula were not up to the demands about to be made on them and of the heavy burden (which he had been shouldering since Rommel’s injury) of combining the duties of C-in-C West with those of Army Group B commander, might well mean that his nerve was in no state to meet a new emergency.
Some last-minute shifts of position within the 84th Corps confirmed that it would be Panzer Lehr and the 5th Parachute Division which would bear the brunt of the carpet-bombing Bradley devised with such care. When this began on 24 July (because the postponement order necessitated by weather conditions did not get through in time) but was not followed up, the 84th Corps believed for a little while that its artillery had smashed a major ground attack, but it was already using up ammunition too fast and complained with increasing sharpness over the next few days that re-supply was not quick enough: a shortage of shells for the tank-killing 88-mm guns at the point of the advancing American salient was particularly noteworthy, and by 27 July von Kluge’s chief quartermaster confessed that he had no stocks at all of some other types. Apart from this, however, and reports of the practical obliteration of Panzer Lehr by the bomb-carpet, ULTRA shed no particular light on the first days of Cobra; purely tactical details were never its strongest suit, and it could seldom keep up with the changing fortunes of a swiftly moving battle.
More advantageous to the Allied commanders was the opportunity ULTRA gave them to monitor von Kluge’s reactions to the pressure upon him. To stop the rot that was setting in, he needed more tanks. Would Hitler let him denude the defenses of eastern Normandy and the approaches to Paris still further? The answer provides a good illustration of the patchwork nature of military intelligence and of the judgment required for the proper use of ULTRA.
The nearest of the still uncommitted panzer divisions was 116th Panzer, which ULTRA had regularly reported between the Seine and the Somme in mid-June. Then it disappeared entirely until 9 July, when it was cryptically told to observe wireless silence until further notice—an order which might (but need not) herald the imminence of a move which it was imperative to keep secret. In fact, the division seems to have stayed where it was but to have remained on the alert until Goodwood led von Kluge to secure Hitler’s permission to move it to Caen on the 19th. Goodwood was called off almost at once, so the 116th Panzer Division remained in reserve for ten more days until (as we now know) the mounting crisis in the west caused von Kluge to put together a striking force consisting of the 116th Panzer and 2nd Panzer Divisions (then south of Caen) under the control of the 47th Panzer Corps and direct it to halt the American advance. At midday on 29 July, only twenty-four hours after this decision was taken, a front line report showed that the 47th Corps had suddenly appeared on the opposite side of the 2nd Parachute Corps from usual; lest this be no more than an error in transmission, a cautious comment was added to the ULTRA signal reporting it: “No other evidence for transfer of the 47th Corps from right to left of the 2nd Parachute Corps.” Positive proof that the transfer had really taken place was not forthcoming until the following afternoon with a new location for the 2nd Panzer and a statement on the 30th that the two panzer divisions were under the command of the 47th Corps.
By this time there was no stopping the Americans’ victorious advance through the gap opened by the collapse of the German front at its seaward end (Avranches fell on 31 July), and a spate of signals told a tale of increasing woe which betokened the disintegration of Seventh Army—“a hell of a mess,” von Kluge called it. ULTRA confirmed the evidence of the victors’ eyes. Ordering all its bombers into the air on 29 July, the 9th Fliegerkorps impressed on the pilots that maximum effort was needed to close the gap and prevent the Allies from scoring a strategic success. The remnants—only two hundred men—of the 243rd Division (which had been in the eye of the storm) had lost all their artillery and transport, and even the divisional staff was on foot. Nearby, the 2nd SS was no better off, and the 116th Panzer had suffered so heavily that on the morning of the 30th it had still not been able to carry out an attack ordered for the previous day. On behalf of both divisions, the 47th Corps kept calling (apparently in vain) for more petrol for stranded tanks, but the 13th Flak Division painted the most lurid picture of the rout. Engaged in ground fighting at Mortain on 1 August and entirely without infantry support, it despaired of saving the guns of its scattered batteries because of an acute shortage of petrol, ammunition and transport, and forecast that they would have to be blown up or left behind. To cap all, its anti-tank grenades were proving ineffective against the thick armor of the American tanks.
On 1 August the U.S. 12th Army Group came into being under Bradley, who promptly let Patton and Third Army off the leash. At first he pointed them into Brittany, but as the situation swiftly developed in his favor Bradley transferred Third Army’s weight into the direction where more dazzling success beckoned—south to the Loire and then east towards Paris. This would anyhow have laid the Germans open to attack on three sides, but a retreat which might still have been comparatively orderly was turned into disaster by Hitler’s sudden decision to launch a counterattack between the rivers Sée and Sélune from Mortain westwards in order to paralyze the American advance by cutting its life-line through Avranches. Patton’s account of his feat in passing two infantry and two armored divisions through the town in twenty-four hours over a single bridge (“one of those things which cannot be done, but was”) shows that there was substance in the Führer’s dream, but Hitler had not reckoned sufficiently with either the difficulty of organizing and nourishing so spectacular an armored assault or with the high risk of encirclement if it failed.
Hitler took his decision late on 2 August. Sensing the risk involved, von Kluge at first demurred, but in the aftermath of the July plot he was in no position to sustain his objections for long, and next day he began to make the re-dispositions which were the necessary prelude to an attack on the scale demanded. Since he would in any case have been likely to take steps to bring order out of the prevailing chaos, and since no Allied intelligence appreciations written at this moment appear to have survived, it is difficult to determine whether von Kluge’s moves, which soon became known through ULTRA, were at first seen as preparations for attack or for a fighting withdrawal. Because neither ULTRA nor any other source had yet given the slightest hint of what they portended, a vital clue was denied those whose duty it was to interpret them. Things like the 47th Corps’ tactical withdrawal on 3 August “to strengthen the resistance of the exhausted troops,” or the 2nd Panzer being pulled out altogether, may in any case have been settled before Hitler’s order and quite independently of it, and will probably have been read as prudential measures only. On 5 August, however, a clutch of Enigma messages, all of which were retransmitted as ULTRA signals between midday and midnight, showed that something more serious was intended. The first showed the 2nd SS Panzer being withdrawn from the line to reassemble between Mortain and Sourdeval, while at the same time the 47th Corps was freed by handing its sector over to the 84th Corps and the 116th Panzer was relieved by the 84th Infantry Division (new to Normandy, and one of several reinforcements which, largely unknown to ULTRA, Hitler had ordered up from the south of France and the Franco-Belgian border the previous week).
Cut the Allies Off
The first positive news that there was to be a major offensive was signaled early on the evening of 6 August, only five hours after the 2nd SS called for fighter protection for a night attack southwest through Mortain (which the U.S. 7th Corps had just captured) towards St. Hilaire; another signal a few minutes later showed that this was part of a 47th Corps drive in which the 116th Panzer, 2nd Panzer and 1st SS Panzer were also to participate, and before long the same formation had revealed the object—to cut the Allies off from their supply base. The importance of the event was underlined by the presence of the 1st SS Panzer, which had been on the Caen front since June and which had been detected assembling round Falaise as recently as the previous night. Ten minutes after midnight on 6-7 August, we could be even more explicit. Seventh Army was to have launched an offensive that evening from Sourdeval and Mortain with the purpose of re-capturing Brecey and Montigny (in the event, it did not do so until a couple of hours after midnight), so that two of these signals at any rate arrived in time to give warning of what was afoot.
ULTRA intelligence was sent to Supreme Headquarters, Army Group and Army commanders (and their RAF and USAAF equivalents), but for security reasons no lower in the chain of command, unless very heavily disguised; it would be interesting to know how much these three signals influenced the dispositions made by Gen. Hodges of U.S. First Army. For it was resistance like that of the 30th Division (which took over responsibility for Mortain barely six hours before the German attack cut off one of its battalions on Hill 317 to the east of the town; the battalion’s obstinate defense, although besieged for five days, is well known), together with heavy bombing raids by both air forces (to which ULTRA certainly contributed targets) which blunted the German offensive within a few hours. That ULTRA helped to tilt Bradley’s judgment towards boldness, and thus contributed towards the tremendous success he gained, is almost certainly implied by his remark that although on the morning of 8 August four of his divisions were still held up north of the Avranches bottleneck “I resolved to take the plunge and strike for the annihilation of the German Army in the west.”
His resolve will quickly have been confirmed by an order issued on the evening of 7 August by Gen. Hausser, the Seventh Army commander, demanding a renewal of the attack and a breakthrough to Avranches. Decoding difficulties delayed the ULTRA signal until the following evening, but a few hours now mattered less than the certainty that the German armor would continue to press westwards while Patton raced east to surround it and Montgomery pushed down towards Falaise to narrow the escape route from the trap Hitler was preparing for his own men.
Bradley reckoned that he needed forty-eight more hours to complete the envelopment, and laid on aerial reconnaissance every hour to discover whether the panzers would turn in retreat before he was ready. To know when they did so was valuable; to know whether and when they intended to do so—something aerial reconnaissance could never discover—was priceless, and ULTRA achieved this in the early hours of 10 August. In his capacity as commander of Army Group B, von Kluge had issued an order (the wording of which made the hand of Hitler plain) the previous evening which called for an attack by six panzer divisions and ancillary arms to be delivered by a specially constituted group under Gen. Eberbach “probably on the 11th,” although it might be postponed.
Agent of His Own Destruction
Eberbach’s objective was to be “the sea at Avranches,” and the fate of the battle of France was said to depend on his success. The signal was in the hands of all the Allied generals concerned by breakfast-time on 10 August—that is, in time to give them twenty-four hours or more to decide how to take maximum advantage of their foreknowledge that the enemy was bent on thrusting his head still further into the noose and so becoming the agent of his own destruction.
This was certainly ULTRA’s greatest triumph of the whole western campaign, for it ensured the historic carnage and destruction of the Falaise pocket, and the loss to Hitler of 50,000 German POWs.
The Author
As a major in the British Army’s Intelligence Corps, Ralph Bennett was responsible for sending signals based on ULTRA decodes to Allied commanders in the field, 1941-1945. President of Magdalene College, Cambridge, his book Ultra in the West, is the only study of 1944-45 based on ULTRA.
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Northwestern France, 1944: The Breakout, Operations, 1-13 August 1944. |
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First Army Breakout, 24 July-4 August 1944. |
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Exploitation, 30-31 July 1944. |
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British infantry moving up during attacks between Hill 112 and Hill 113 in the Odon valley, 16 July 1944. |
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Sherman tanks of the Staffordshire Yeomanry, 27th Armoured Brigade, carrying infantry from 3rd Division, move up at the start of Operation 'Goodwood', 18 July 1944. |
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U.S. infantrymen examine the possessions of German casualties in the town of Notre Dame de Cenilly at the beginning of Operation Cobra. |
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Elite German Fallschirmjägers of the 5th Parachute Division, such as this one armed with rifle and stick grenade in a foxhole, fought stubbornly against the advancing Americans. |
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Exhausted GIs of the 120th Infantry Regiment pose for a war photographer after their tenacious defense of Hill 314 during the Battle of Mortain. |
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Panzer troops of the German 2nd Panzer Division service their anti-tank gun during the German counterattack at Mortain. |
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A German casualty next to a halftrack destroyed by aircraft, Mortain, August 1944. |
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British 5.5-inch medium gun firing at night during the offensive in the Odon valley near Evrecy, 16 July 1944. |
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A P-47 Thunderbolt roars over a column of American tanks on a French road. Brig. Gen. Otto Weyland detailed a four-aircraft flight of P-47s to cover each of Patton’s armored columns in Brittany. |
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German Tiger I tank of 3./s.Pz.Abt. 503 (3rd Company 503rd Heavy Tank Battalion) which was overturned at Manneville during the Allied heavy bombing at the start of Operation 'Goodwood', 18 July 1944. |
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A Churchill Mk IV or VI tank awaits possible enemy counterattack in a ruined Normandy village, July 1944 |
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U.S. troops move to the line for Operation Cobra. |
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U.S. troops during Operation Cobra. |
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U.S. troops in Operation Cobra. |
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The crew of an M4 Sherman tank pursues retreating German forces in northwestern France. |
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Tanks of the 2nd Armored Division pass through the lines of the 120th Infantry Regiment, 30th Infantry Division July 26, 1944 near St. Lo, France. |
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Tanks of the 2nd Armored Division pass through the lines of the 30th Infantry Division and roar into the breach near St. Lo. |
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U.S. bomber crews inadvertently inflicted casualties on front-line U.S. troops when some of their bombs fell short during Operation Cobra; nevertheless, they shattered the German defenses. |
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Infantrymen scramble to dig out soldiers trapped in their foxholes after the bombing. |